Adjusting inputs to give outputs closer to a level playing field is what you do in sports (handicap). We know their statistical models are decent because even with handicaps in place, they become more "racist" as the data set grows larger. Of course it's a game of cat and mouse, and eventually they'll plug up the holes. Right now they're trying to tie up the loose ends with search engines and indexed data in hopes they can keep Pandora's box closed in time to think of a solution.